Barry Eastbrook has a book "Tomatoland" [1], about the taste of tomatoes in America, which is based on his earlier article [2]. Also there was a good interview with him on NPR [3]. Tomatoes are grown for easy transportation, and appearance, not for taste. They're harvested while still green, and then treated with ethylene gas, which "colors" them in an attractive color, but doesn't add any taste.
1. http://www.amazon.com/Tomatoland-Industrial-Agriculture-Dest...
2. http://www.gourmet.com/magazine/2000s/2009/03/politics-of-th...
3. http://www.npr.org/templates/transcript/transcript.php?story...